Its 15(3+4h)
In this case h can be anything, so lets say it 7
h=7
45+60h=465
So we know it equals to 465, so if an equation looks different but has the same answer we will know that its the same number (465).
105h=735
675h=4725
15(3+4h)=465
15(30+45x)=5175
The only one that has the answer 465 is 15(3+4x)